/// <summary>
/// Function to perform a comparison of an item name to the name specified, using the filter type specified.
/// </summary>
/// <param name="name">The name to look up.</param>
/// <param name="itemName">The name of the item to evaluate.</param>
/// <param name="filterType">The type of filter to apply.</param>
/// <param name="comparisonType">The type of string comparer to use.</param>
/// <returns><b>true</b> if the resource name matches the filter type, or <b>false</b> if not.</returns>
private static bool NameComparison(string name, string itemName, LocateFilterType filterType, StringComparison comparisonType)
{
if (string.IsNullOrWhiteSpace(itemName))
{
return(false);
}
switch (filterType)
{
case LocateFilterType.StartsWith:
return(itemName.StartsWith(name, comparisonType));
case LocateFilterType.EndsWith:
return(itemName.EndsWith(name, comparisonType));
case LocateFilterType.Contains:
return(itemName.IndexOf(name, comparisonType) != -1);
case LocateFilterType.NotContains:
return(itemName.IndexOf(name, comparisonType) == -1);
case LocateFilterType.NotStartsWith:
return(!itemName.StartsWith(name, comparisonType));
case LocateFilterType.NotEndsWith:
return(!itemName.EndsWith(name, comparisonType));
case LocateFilterType.NotEqual:
return(!string.Equals(name, itemName, comparisonType));
default:
return(string.Equals(name, itemName, comparisonType));
}
}
/// <summary>
/// Function to locate a graphics resource by its name.
/// </summary>
/// <typeparam name="T">The type of graphics resource to look up. Must inherit from <see cref="GorgonGraphicsResource"/>.</typeparam>
/// <param name="graphics">The graphics instance that was used to create the resource.</param>
/// <param name="name">The name of the resource to find.</param>
/// <param name="filterType">[Optional] The type of filter to apply.</param>
/// <param name="comparisonType">[Optional] The type of string comparison to use for name comparison.</param>
/// <returns>An enumerable containing the resources with names that match the filter type.</returns>
/// <exception cref="ArgumentNullException">Thrown when the <paramref name="graphics"/> parameter is <b>null</b>.</exception>
/// <remarks>
/// <para>
/// Each instance of the <seealso cref="GorgonGraphics"/> keeps a weak registration of each objected inheriting from <see cref="GorgonGraphicsResource"/> that was created during the lifetime of the
/// application. Using this registration an application can look up any previously created resource (assuming it's not been collected, or disposed) should it be necessary.
/// </para>
/// <para>
/// <note type="important">
/// Resource names are not required to be unique. Therefore, searching for the name may result in multiple items being returned in the enumerable.
/// </note>
/// </para>
/// </remarks>
/// <seealso cref="GorgonGraphicsResource"/>
public static IEnumerable <T> LocateResourcesByName <T>(this GorgonGraphics graphics,
string name,
LocateFilterType filterType = LocateFilterType.Equal,
StringComparison comparisonType = StringComparison.CurrentCultureIgnoreCase)
where T : GorgonGraphicsResource
{
if (graphics == null)
{
throw new ArgumentNullException(nameof(graphics));
}
if (string.IsNullOrWhiteSpace(name))
{
return(Enumerable.Empty <T>());
}
return(graphics.GetDisposables()
.Select(item =>
{
// If the object has been collected/disposed, then do nothing.
if ((!item.TryGetTarget(out IDisposable disposable)) ||
(!(disposable is T resource)) ||
(resource.IsDisposed))
{
return null;
}
return !NameComparison(name, resource.Name, filterType, comparisonType) ? null : resource;
})
.Where(item => item != null));
}
